The changed situation in early 1942

As the daylight Axis air raids on Malta grew fewer and smaller, there were more raids at night. These were opposed by Beaufighters of No. 1435 flight, acting as night fighters. By May 1942, the tonnage of bombs dropped on Malta had fallen to 520 tons, which still as great as the highest month in 1941. Probably the greatest hazard in this period were Axis minefields laid by "fast German motor-boats". They had laid 600 mines and 400 anti-minesweeping devices around Malta since February 1942. These were effective, as one or two British submarines were lost to mines. While the Welshman trip had helped the ammunition supply, the island was still in danger and could be lost if the June convoy failed. This is based on the account in Vol.III of the Official History.